The blood test apparatuses disclosed in Patent Document 1 and Patent Document 2 have been known as conventional blood test apparatuses.
FIG. 1 is a cross sectional view of a conventional blood sensor, and FIG. 2 is a plan view of a substrate constituting this blood sensor.
As shown in FIG. 1, blood sensor (or “sensor”) 1 has a plate-like base body 2.
Blood storing section 3 is formed in approximately the center of base body 2. In addition, supply path 5 that supplies blood in storing section 3 to air hole 4 is provided in base body 2. One side of supply path 5 is coupled to storing section 3 and the other side is coupled to air hole 4. In addition, base body 2 is provided with detection electrodes 6 to 9 provided on the lower surface side of supply path 5 and connection electrodes 6a to 9a drawn, respectively, from these detection electrodes 6 to 9.
Base body 2 is composed of substrate 10 having an upper surface on which detection electrodes 6 to 9 and connection electrodes 6a to 9a are provided, spacer 11 that is provided on the upper surface side of substrate 10 and has a slit constituting part of supply path 5 and cover 12 provided on the upper surface side of spacer 11.
As shown in FIG. 2, wires in substrate 10 are respectively drawn to connection electrodes 6a to 9a formed in the end part 10a side of substrate 10 through detection electrodes 6 to 9 provided in substrate 10.
FIG. 3 is a cross sectional view of the blood test apparatus in which the above-described sensor 1 is mounted.
As shown in FIG. 3, blood test apparatus 17 has housing 18 having an approximately rectangular solid shape. Puncturing section 19 composed of upper holder 19a and lower holder 19b is provided in one corner of housing 18. Laser puncturing unit 20 is incorporated to face puncturing section 19.
Sensor cartridge 21 is removably inserted beside laser puncturing unit 20, and sensors 1 are stacked and stored in sensor cartridge 21. In addition, electrical circuit section 22 that measures the properties of blood 16 is arranged in parallel with sensor cartridge 21. Battery 23 is removably accommodated above laser puncturing unit 20, sensor cartridge 21 and electrical circuit section 22.
Puncturing button 20a to drive laser puncturing unit 20 is provided on upper surface 18b of housing 18, and skin detecting sensor 24 is provided in the vicinity of puncturing section 19 in the lower part of housing 18. In addition, a display section (not shown) is connected to electrical circuit section 22.
Now, operations of blood test apparatus 17 configured as described above will be explained.
First, slide plate 21a provided below sensor cartridge 21 conveys the bottom sensor 1 among sensors 1 stacked and stored, to puncturing section 19. Conveyed sensor 1 is sandwiched and fixed between upper holder 19a and lower holder 19b. 
Next, the patient contacts puncturing section 19 with skin 15. This contact with skin 15 is detected by skin detecting sensor 24 provided in the vicinity of puncturing section 19 in housing 18. Puncturing is permitted by detecting the contact with skin 15. The patient then presses puncturing button 20a. When puncturing button 20a is pressed, laser light 20b is emitted from laser puncturing unit 20 and punctures skin 15.
Blood 16 exudes from skin 15 by puncturing skin 15. Exuding blood 16 is taken into sensor 1. Blood 16 taken into sensor 1 flows from storing section 3 into supply path 5 and is detected by detection electrodes 6 to 9. Signals detected in detection electrodes 6 to 9 are guided respectively to connection electrodes 6a to 9a and transmitted to electrical circuit section 22 through connection electrodes 6a to 9a. Electrical circuit section 22 measures components (e.g. a blood sugar level) of blood 16. Electrical circuit section 22 displays measurement results on a display section (not shown).
The puncturing apparatus described in Patent Document 2 has a detecting switch that detects swelling of skin in the apparatus and detects appropriate contact with skin by the detecting switch. The detecting switch is provided in a cylindrical part and has a movable body and a bracket each having a switch terminal. The movable body is pivotally supported by the shaft of the bracket and configured to change the position of the switch terminal. This movable body has a downward taper surface. When skin swells in the cylindrical part, the detecting switch rotates so as to allow the movable section to be lifted up by skin. By this means, the switch terminal of the movable body is shifted upward, and therefore, contacts the switch terminal of the bracket. As a result of this, the detecting switch is turned on and detects the contact with skin.    Patent Document 1: Japanese Patent Application Laid-Open No. 2004-4046    Patent Document 2: International Publication No. WO 2004/054445 Pamphlet